powertap SL chain suck

midastouch said:

Hey,
I've got a new Powertap SL and when I coast I occasionally get chain suck. I've only got a few miles on it, so can I expect the freehub to loosen up or is this something that needs service? Anybody else had this occur?
Any help appreciated.

Mike

Weird, and definitely not normal. Take the freehub off and inspect the bearings and pawls to see what is holding it up. Inspect the grease seals in the freehub bearings. If it is obviously stiff, don't poke around in it too much and just get it warrantied.

Just taking a stab at this . . . you may want to check the clearance between the large cog carrier and your spokes. When mine was new and the spokes loosened a bit, the rivets on the large cog carrier would occassionally catch on the spoke "elbow" as it turned into the hub flange and cause the freehub to stop turning while coasting -- causing a chain suck effect. I spaced the cassette out just a touch and kept an eye on the spokes until they fully seated. I've never had this happen on any other wheel, but I've never had a road hub with flanges as tall the the PT's.

BTW, this drove me nuts the first ride it happened. I stopped and pulled the wheel and the freehub turned fine in my hand or as I hold the bike in the air -- then I check the chain, etc. I only realized that once my body weight was on the bike, it would tension the spokes and allow the cassette to contact it.

JIM WV said:

. . . you may want to check the clearance between the large cog carrier and your spokes.

If you're riding Shimano 10-sp ensure you've got the thin spacer on the freehub body before sliding the cogset on. Well, for Dura-Ace at least I need it.

F1_Fan said:

If you're riding Shimano 10-sp ensure you've got the thin spacer on the freehub body before sliding the cogset on. Well, for Dura-Ace at least I need it.

What about the spacer inside the freehub, on the axle to space the freehub out from the hub body? This may also be useful.

Thanks for all the feedback. I'm still riding 9-speed, so the spacer wasn't the issue, nor spoke heads hitting cassette. I did an easy hour ride today (I live in Florida) and it seems to have healed itself. I guess it just needed a short break-in. Perhaps the hub had been sitting on the shelf for a bit and just need the grease re-distributed. Anyway, it works now.